This may well be the first magazine article engine designed by Elmer Wall!  At least it was the first offering in a magazine published in 1929.  The construction articles for this engine spanned two issues, first covered the crankcase, cylinder and internal parts, the second installment covered a float type carburetor which would be built from  small aluminum castings.  You must understand here that Mr. Wall was breaking ground in model engineering, he had no prior art to copy, he is literally the father of model engineering in this country and had to figure these tiny parts out for himself and then express this knowledge to beginning craftsmen who would read his magazine article!  As a machine project, a relatively easy project for an advanced beginner of average talents, mabye a little strong for a first attempt beginner but not impossible either.  The engine described in the reprint article was built on a 6" lathe and small drill press.

The construction notes are from 1929! by an actual miniature engine designer and pioneer in the field of model engineering named Elmer Wall and are from a magazine known as "Modern Mechanics and Inventions". 

Historically, this is one of the "Missing Wall Engines" described by Reed Martin in his outstanding collection of Wall Engines & his display which he shows at meets such as "Cabin Fever Expo".   You can see for yourself at the following website! This is the lower center engine in the photos on the "missing engines board".

 modelenginenews.org/      Just go to the site and search for ELMER WALL or REED Martin!

The Drawings are High Resolution copies which were adjusted for gamma, brightness and contrast to correct the  paper bag dark brown foxing in the original print.  The originals were so brittle that they would break or crack if allowed to sag too far under their own weight! The magazine format was a much smaller and difficult to read so we have expanded to nearly 8 1/2 x 11 format for easy reading, paper is white high brightness 24 pound  bond.  You will not see the Moire pattern present in the scans, these are halftone dot prints from the magazine and look very nice but do not scan or photograph well for the ebay electronic presentation. There are 6 pages in all that cover the complete engine, casting machining, small parts, carburetor, ignition points!  The 4 images in the listing pictures are actual scans from the set of drawings in the offer.